Deep within the mountain belly, an ancient portal unexpectedly opens, and a field operative is sucked into it. To rescue companions and explore the unknown world behind the gate, archaeologist Yan Qi is urgently dispatched to Kunxu Mountain. The moment he steps into the mountain belly, he is surprised to find that the relief carvings on the stone gate are identical to the remnant map he has been tracking for three years. For the truth, Yan Qi without hesitation joins the team exploring the world behind the gate.